help cutting through 3 inches of benchtop

[Mike Steinhilper]

i'm working on my new benchtop, which is 2 mdf sheets sandwiched between 2 birch plywood sheets. Thickness is almost 3 in. My circ saw will do about 2 1/2. I'm putting a band around it so i need a clean cut, so i'd rather not cut halfway and flip it over. any ideas?

[Greg Hines, MD]

I did the same kind of thing with my benchtop, which is 4 layers of 3/4" plywood. I used a long straight edge, and a router with a Bosch 1/2" bit, that is about 4" long, with at least 3" of cutting length. Go in stages, about 1/4" in each step, and it will leave a nice smooth edge for your banding.

Doc

[Pat Germain]

Do you have a reciprocating saw? If not, you can rent them cheap. I would think using a guide and a very fine wood blade would give you a nice cut.

[Jamie Buxton]

With just the circular saw... Cut 2 1/2" deep from the top. Flip it over and cut the remaining 1/2" from the bottom, but be sure to offset this kerf toward the middle of the table. Now when you glue the edge banding on, it will be certain to bear on only the 2 1/2" face. That it isn't quite bonded to anything for the bottom 1/2" doesn't matter.

Or if you have a router too.... Make the cut from the top. Flip the top and cut through the remaining part of the top, but in this method, offset the underside kerf slightly to the outside of the first kerf. Now put a flush-cutting bit in your router -- the kind with a bearing at the tip -- and trim the underside kerf flush with the topside kerf.

[Brian Willan]

i'm working on my new benchtop, which is 2 mdf sheets sandwiched between 2 birch plywood sheets. Thickness is almost 3 in. My circ saw will do about 2 1/2. I'm putting a band around it so i need a clean cut, so i'd rather not cut halfway and flip it over. any ideas?

Find someone who has an 8-1/4" circular saw and borrow it. That should be able to handle that depth of cut you require. If not check out your local rental center and see if they have a larger capacity circular saw.

Barring that, I agree with the reciprocating saw suggestion and clean the cut up with a router and a straight edge.

Cheers

Brian

[Rich Engelhardt]

Hello,
I've tried more than a few times to get a nice clean cut with my Bosch recip. saw. - didn't work out no matter what blade I used. The saw just wanders too much & the blades flex too much also.

I did have a similar situation once w/my old B&D 5 1/2" circ saw.
I cut as deep as I could w/the B&D and finished the cut off by hand.
The slight nub that was left came out easy with a few strokes of a Sure form block rasp.

[Craig D Peltier]

You can rent a beam saw.Large circular saw.

[Reed Wells]

You can rent a 10" Milwaukee or a 15" Makita, though the Milwaukee will follow a guide better.

[john bateman]

I guess it's too late now, but when I made my mdf sandwiched by plywood, I cut the the MDF to size on the table saw for good square edges. Then cut the plywood pieces about 1/8" oversized. After the glue dried, I just used a flush trimming bit in the router to make each plywood side the same as the mdf center.

[Doug Shepard]

...
Or if you have a router too.... Make the cut from the top. Flip the top and cut through the remaining part of the top, but in this method, offset the underside kerf slightly to the outside of the first kerf. Now put a flush-cutting bit in your router -- the kind with a bearing at the tip -- and trim the underside kerf flush with the topside kerf.

That's the method I used on a 4" thick top and it worked great.

[Wilbur Pan]

Why not use your circular saw to saw the first 2 1/2 inches, then get a hand saw to cut through the remaining 1/2 inch of plywood? If you're worried about sawing straight, you'll have a built in 2 1/2 deep saw guide. And you can plane or sand down any bits that still might be proud of the surface fairly easily.

This message brought to you courtesy of Jim Becker's Neanderthal stealth campaign (http://www.sawmillcreek.org/showthread.php?p=784729&#post784729). ;)

[Anthony Whitesell]

I was going to suggest cutting as far through it as possible with the circular in three passes both on the top. Make the first pass at the right length and the second a kerf width wider. Then flip over the top and cut through at the second pass from the top side cuts. This should leave a small overhang, ledge, extra, whatever you want to call it. Then use the router with a flush trim bit to trim the bottom to size.

When I built my router table (2 plys of 3/4 particle board, and 1 1/2 plywood) , I also wanted the edges banded and my table saw could not cut through the thickness of the top (old saw 8 1/2" blade). This is how I got clean and square edges my router table top.

[J. Z. Guest]

I'd go to my local Ace Hardware or Home Depot and rent a bigger circ saw, as a previous poster mentioned.

It is one of those tools you don't need often, but when you do, it saves all kinds of headaches.

Leave it a little oversize, then belt sand it to remove the saw marks. The router with flush trim bit will want to tear out the plywood, but you could back up the cut and do it anyway if you simply must have the cleanest end of bench.

[Rob Will]

I would cut it 1/8" oversize then use a straight edge and a router to trim the top. Then flip it over and use a flush trim bit with a bearing. The first cut is your reference for the second cut.

With a good solid straight edge, a router will give you a better cut than either a circular saw or a hand saw.

I use one of these. The wood surface looks like glass.

Rob